Several methodologies have been developed for introducing transgenes into plants to study gene functions. In general, these systems for producing transgenic plants have some common features: (1) a gene delivery system, (2) a selection system to differentiate transformed cells or plants from untransformed ones, and (3) a regeneration procedure to produce an entire plant (often fertile as well). Among all systems used, Agrobacterium-mediated gene transfer and particle bombardment (in tissue culture) have been popular in recent years to generate transgenic plants.
Traditionally, cloning of vectors for transgenic plants using restriction enzymes and ligases has been time consuming and labor intensive, partly because specific cis- and/or trans-elements are required for different plants, and often for different pant parts/tissues. Polymerase Chain Reaction (PCR) has been used extensively for cloning. However, vectors generated using PCR require sequencing confirmation due to the error-prone nature of PCR. Recently, site specific recombinases and transposases have been developed for general cloning. However, their application for vector assembly for transgenic plants has provided limited success.
Thus, there remains a need to provide a high-throughput vector assembly method for transgenic plants.